Lapping block



F. F. HILLIX LAPPING BLOCK Dec. 17, 1935.

Filed April 19, 1935 [f1/06H07? F05 TEE F. H/LL/x vf MM Patented Dec. 17, 1935 UNITED STATES PATENT oFElcE LAPPING BLOCK Foster F. Hillix, Lakewood, Ohio, assigner to The American Steel and Wire Company of New Jersey, a corporation of New Jersey Application April 19, 1935, Serial No. 17,319 6 Claims. (C1. 51-205) This invention lrelates to lapping blocks, and Referring more particularly to the drawing, more particularly to those which are used for the numeral I designates a block which is comgrinding and/or polishing relatively hard surposed of any suitable material, preferably nonfaces, such as metal or glass, whether plane or metallic and non-hydrous; for instance, a durable curved. liber, or bakelite. This block I may be of any 5 Heretofore it has been the practice, in obtainsuitable shape (being shown in the present ining smooth surfaces, to reduce the same by cutstance as rectangular), and is provided with a k ting or lapping operations employing Wheels, plurality of recesses 2 in each of which there usually of the abrasive variety, and lapping heads, is disposed one of the novel cutting elements of io wherein the cutting is done by a multiplicity of the invention. These cutting elements, which are 1o cutting points of 'irregular shape. The surfaces indicated in the drawing at 3, are in the form of thus obtained are characterized by having an unpacked metallic wool, of which that grade known evenness identified by such terms as grain as Commercial No. 060 steel Wool is found very marks, orange peel, etc., Which depends, in suitable. part, upon the neness, or coarseness, of the For certain grades of finish I have found it wheel and/ or abrasive employed. Coarse wheels advantageous to mix other and softer fibers with and abrasives are employed initially because they the metallic Wool fibers. As an example, the remove the stock rapidly, and finer wheels and/ or softer fibers may be sheeps wool, cotton, linen, or abrasives substituted therefor until the desired hemp, in varying proportions; that is, for the 2o high finish is obtained. rougher cuts it is only necessary to mix a few of 20 One of the worst disadvantages of lapping the softer fibers with the metallic wool fibers; blocks heretofore used is that hard particles that while for the finishing cuts a larger number are are broken off, or cut from, the surface of the included. object being ground and/or polished become en- Whether the metallic wool fibers are used alone, trapped between the same and the lapping block, or in combination with the softer fibers, they producing a scoring or marring effect. If, for preferably protrude slightly from the recesses 2, example, a roll is being polished, and such scoring as shown at 3e. takes place, the resulting effect is in the form of In order to pack the cutting elements 3 tightly a comparatively deep serpentine groove, which into the various recesses 2, they are first rolled may only be removed at the cost 0f considerable into rods of cylindrical shape, as shown in Figure 30 time, labor and material. l, and in such a manner that as many of the fibers It is one of the objects of the present invenas possible are extended in one direction; that is tion to provide a novel lapping block for grinding to say, longitudinally of the roll. Each of these and/or polishing surfaces, such as metal, glass, small rolls of fibers 3 is placed in a cylinder or 55 etc., which presents to the work-piece a rigid tube 4, as shown in Figure 4. 35 cutting member, and one which does not merely The cylinder or tube 4 is then placed over one grind off the irregular surfaces; but, on the other of the recesses 2 in the block I and forced therehand, produces a at smooth surface of high into by means of a plunger 5, which is struck with finish, which is free from the usual defects, such a mallet or other soft hammer. The cutting eleas orange peel", etc. ments 3 are then sheared off at their outer ends 40 Another object is the provision of a device of in such manner as to protrude therefrom, as the class described which may be easily and stated previously. After all of the recesses 2 cheaply manufactured, and one which will prove have been filled, the block I is preferably imvery durable in service. mersed in a liquid binder which is adhesive and These and further objects will be apparent after insoluble in the particular material used as a 45 referring to the drawing, in which: lubricant in the grinding and/ or polishing opera- -Figure 1 is a plan of the device of the invention. tions. Some suitable binders are bakelite, res- Figure 2 is an elevation. inoid, shellac, silicate of soda, waterproof glue Figure 3 is a sectional view on the line III- III (such as casein glue or animal glue), vulcanized of Figure l. rubber, some of the harder varieties of wax and 50 Figure 4 is a sectional elevation showing a low-melting-point solder. The block I is kept means of assembling one of the elements. immersed in the liquid binder until it has com- Figure 5 is an enlarged detail. pletely filled all of the interstices of the fibers in Figure 6 is a perspective of the device in the recesses 2, after which it is removed and al- 'Dv operation. lowed to dry and harden. 55

. binder, and

-to impart this desired Abe utilized. The

If necessary, the previously immersed block I can then be baked to secure additional hardness. For example, bakelite resinoid has been found by experiment to be a very sati-sfactory When baked to a temperature of 300 degrees F. is sufficiently polymerized to have the desired characteristics. This binder having formed into a solid mass, completely fills the interstices between the fibers -of the cutting elements 3 and serves -a dual purpose; first, in that it maintains the fibers in a vertical position, thereby preventing them from bending over in the manner of the bristles of a brush; and secondly, in that it is porous and portions thereof between the fibers break ofi or wear away, leaving cavities or cut-out portions 6 in the faces 'l of the cutting elements 3. These cavities 6 serve to retain the cutting from the surface of the object being ground and/or polished, and result in the prevention of marring, or scoring. Y

The metallic wool fibers, whether used alone or in combination with the softer fibers, are thus Vheld in a vertical position toV produce Va buffed or -mshedV surface by actual cutting, rather than produce an unevenness of the type previously reorange peel, which, 'while sometimes apparent to the eye, is more frequently too minute to be perceived.

In practice, one or more blocks I, with the cutting elements 3 protruding therefrom, as at 3a,

ished. Referring to Figure 6 of the drawing, a machine is disclosed which satisfactorily serves movement. This machine having a plurality of rewhich one of the blocks I is adapted to seat. A satisfactory method of retaining the blocks I in the recesses I2 is by the use of glue, although mechanical expedients may holder I 0 is journaled in any suitable manner to one end of a shaft I 3, which is connected on its other end to a shaft I4, by means of a coupling I5. The shaft I4 is reciprocablysupported in any suitable manner by a suitable frame (not shown). An unbalanced pulley comprises a holder IIJ cesses I2 in eachvof I6 is connected to the shaft I3 and driven through a power belt I1 from a suitable prime mover. Upon rotation of the unbalanced pulley IS the blocks I are oscillated in a manner very suitable for grinding and/or polishing. A suitable loose abrasive is employed between the blocks I and the workpiece in order to facilitate the grinding and/or polishing. This abrasive is preferably used with oil or emulsion.

While I have shown and described several specinc embodiments of my invention, it will be understood that I do not Wish to be limited exactly thereto, since various modifications may be made without departing from the scope of my invention, as defined in the following claims.

I claim: l. A lapping block comprising a body having at least one recess, and fibrous material disposed in and protruding from said recess, said fibrous materialbeing composed of at least some metal fibres.

2. A lapping block comprising a body having at least one recess, and fibrous material disposed in and protruding from said recess, said fibrous material Ybeing composed of at least some metal fibers and impregnated with a binding agent.

3. A lapping block comprising a body having at least one recess, and fibrous material disposed in and protruding from said recess, said fibrous material being composed of a mixture of metallic and vegetable fibers.

4. A lapping Vblock comprising a body having at least one recess, andflbrous material disposed in and protruding from said recess, said fibrous material being composed of a mixture of metallic and animal fibers.

5. A lapping block comprising a body having at least one recess, and fibrous material disposed in and protruding from said recess, said fibrous material being composedY of a mixture of metallic and vegetable binding agent.

6. A lapping block comprising a body having` at least one recess, and fibrous material disposed in and protruding from said recess, said fibrous material being composed of a mixture of metallic and animal fibers impregnated with Va binding agent.

FOSTER F. HILLIX.

fibers impregnated with al soy 

